Hi, When -Wextra is used, gcc emits many warnings about an empty 'if' or 'else' body, like this: ../fs/posix_acl.c: In function ‘get_acl’: ../fs/posix_acl.c:127:22: warning: suggest braces around empty body in an ‘if’ statement [-Wempty-body] /* fall through */ ; ^ To quieten these warnings, add a new macro "do_empty()". I originally wanted to use do_nothing(), but that's already in use. It would sorta be nice if "fallthrough" could be coerced for this instead of using something like do_empty(). Or should we just use "{}" in place of ";"? This causes some odd coding style issue IMO. E.g., see this change: original: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) /* fall through */ ; with new macro: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) do_empty(); /* fall through */ using {}: if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) {} /* fall through */ or { /* fall through */ } or even if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) { /* fall through */ } or if (cmpxchg(p, ACL_NOT_CACHED, sentinel) != ACL_NOT_CACHED) { } /* fall through */ drivers/base/devcoredump.c | 5 +++-- drivers/dax/bus.c | 5 +++-- drivers/input/mouse/synaptics.c | 3 ++- drivers/target/target_core_pscsi.c | 3 ++- drivers/usb/core/sysfs.c | 2 +- fs/nfsd/nfs4state.c | 3 ++- fs/posix_acl.c | 2 +- include/linux/kernel.h | 8 ++++++++ sound/drivers/vx/vx_core.c | 3 ++- 9 files changed, 24 insertions(+), 10 deletions(-)